More from WebMD

June 11, 2012 -- Self-injury is a common emotional disorder among teens and young adults, and now new research confirms that young children also injure themselves on purpose.

In one of the first studies ever to assess self-injury rates among children as young as age 7, close to 7% of 3rd grade girls and 8% of 3rd grade boys said they had self-injured at some point in their lives.

In past studies, self-injury rates have been reported to be as high as 20% among high-school-aged teens and almost 40% among college students.

Self-injury was defined in the new study as cutting, carving, burning, piercing, or picking at the skin, or hitting oneself to cause pain, but not death.

Cutting Most Common in Older Girls

Interviews with 665 children and teens between the ages of 7 and 16 revealed key differences in patterns of non-suicidal self-injury by age and gender.

Among the major findings:

Prior to high school, boys were as likely to self-injure as girls. But by ninth grade, girls were three times more likely to report the practice as boys.

Girls were four times as likely as boys to report cutting or carving the skin as their method of self-injury, while boys -- especially younger boys -- were more likely to report self-hitting.

1.5% of the children interviewed reported engaging in non-suicidal self-injury at least five times over the previous year.

The study did not examine whether self-injury is more common among teens and younger children than it once was, but researcher Benjamin L. Hankin, PhD, says it is generally agreed that it is.

"The study of self-injury is relatively new, so we don't really have good data to confirm it, but just about everyone who treats these children will tell you this alarming behavior is on the rise," the University of Denver associate professor of psychology tells WebMD.

Self-Injury Awareness May Add to Problem

Steve Pastyrnak, PhD, division chief of pediatric psychology at Helen DeVos Children's Hospital in Grand Rapids, Mich., says increased awareness of self-injury and greater attention from the media may be contributing to the problem.

Online videos of teens engaging in self-injury have become common on YouTube, and a recent analysis of the trend found that just 1 in 4 of the most commonly viewed videos sent a clear message against the practice.

While some children self-injure solely to gain attention, Pastyrnak says that most say it brings on a sense of calm or helps them cope with negative emotions.

"Self-injury is typically done for stimulation or soothing," he says. "It is, in a sense, treating emotional pain with physical pain. Some children say they need the pain because they feel emotionally numb."

He adds that self-injury is a red flag that a child or teen may be suffering from depression or anxiety. Self-directed aggression appears to be a form of the "fight or flight" response.

Teach Kids Coping Skills

In his practice, Pastyrnak teaches children and teens strategies for dealing with anxiety and stress, such as breathing in slowly through the nose and out through the mouth or tensing and holding the muscles and then relaxing.

Another strategy is what he calls his version of the "Jedi mind trick."

"We teach kids to replace negative thoughts with positive ones such as, 'I feel good today,' or 'I will have fun today,'" he says. "It helps them let go of the negative emotions."